安徽铜陵矿集区海底喷流沉积体系的流体包裹体微量元素对比  

Trace Elements in Fluid Inclusions of Submarine Exhalation-Sedimentation System in Tongling Metallogenic Province

作　　者：徐九华[1] 谢玉玲[1] 杨竹森[1] 蒙义峰[2] 曾普胜[2] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]中国地质科学院矿产资源研究所,北京100037

出　　处：《矿床地质》2004年第3期344-352,共9页Mineral Deposits

基　　金：国土资源部专项研究计划 (编号 :2 0 0 10 10 3 )之项目二"铜陵矿集区三维蚀变填图与流体示踪研究"资助

摘　　要：铜陵矿集区与铜_金 (多金属 )矿床有关的热液活动主要有两大体系 ,即与海西期海底喷流沉积有关的热液体系和与矽卡岩矿化有关的燕山期岩浆热液体系。查明这两类热液体系的流体包裹体特征对区域找矿和矿床成因研究都有实际意义。在包裹体岩相学研究基础上 ,应用ICP_MS技术和热爆提取方法 ,研究了新桥、冬瓜山、峙门口、铜官山、朝山等矿床具代表性的热液石英中流体包裹体的微量元素、稀土元素特征。结果表明 ,两类热液体系在流体包裹体特征上有较大的区别 ,在流体的微量元素和稀土元素特征方面也很不相同。海底喷流沉积体系的热液石英中流体包裹体与岩浆热液体系的相比 ,稀土总量较高 ,LREE/HREE比值较大 ,δEu不明显 ,且Mo/ (W +Sn)比值较高 ,反映流体中成矿物质的深源特征 ;Ga/Tl、Rb/Cs大 ,Zr/Hf低 ,也不同于岩浆热液体系。Hydrothermal fluids related to copper_gold (polymetallic) deposits in Tongling Metallogenic province can be classified into two types, i.e., fluids associated with Hercynian submarine exhalation_sedimentation and those related to skarn alteration during Yanshanian magmatic movement. Two systems are recognized on the basis of characteristics of fluid inclusions, especially those of trace elements and rare earth elements in fluid inclusions. With ICP_MS and heating_decrepitation techniques, the authors studied fluid inclusions in quartz samples from such deposits as Xinqiao, Dongguashan, zhimenkou, Tongguanshan and Chaoshan so as to probe into rare earth elements and other trace elements. The results show that fluid inclusions in quartz of the submarine exhalation_sedimentation system have higher ΣREE, larger LREE/HREE than those of the magmatic hydrothermal system. The Eu anomaly is not clear in the submarine exhalation_sedimentation system. The Mo/(W+Sn) ratios are relatively high, indicating a deep source of ore materials in the submarine exhalation_sedimentation system. High Ga/Tl, large Rb/Cs and low Zr/Hf are also different from the corresponding values of the magmatic hydrothermal system.

关 键 词：地球化学 海底喷流沉积 流体包裹体 ICP-MS 微量元素 

分 类 号：P591[天文地球—地球化学] P599[天文地球—地质学]